Construction Surveying & Layout
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Introduction | Table of Contents | Back Cover

Preface

Your community library probably has several books on surveying. Many have been written. But nearly all are technical and detailed, offering far more theory and much greater depth than builders and contractors need. That's too bad, because most builders and many tradesmen need a working knowledge of basic survey principles.

On every job someone has to find or verify the location of lot corners, align foundation, walls and floors, lay out perpendicular and parallel lines, mark angles, set grade or calculate cut and fill quantities. Professional surveyors can do this work, of course. But you don't need to hire a professional to check a boundary line or lay out a driveway. After reading this manual, I think you'll agree that most of the survey and layout work on a construction site is relatively easy. Anyone with the desire and time available can master the skills required.

This manual should meet your needs precisely if you want to learn construction surveying and layout, but don't have the patience to wade through a detailed, theoretical surveying text. I'll emphasize the practical rather than the theoretical and focus on the type of survey and layout problems you're likely to face on your next job.

If knowing how to make a simple survey will help in your construction work, you're reading the right book. I'll cover all the practical surveying and layout you're likely to need for any construction project. If you're concerned that your math skills may not meet the challenge presented by the more complex survey problems, don't worry. I've simplified the trigonometry, geometry and mathematics throughout this volume. If you come to a symbol or calculation you don't understand, a little study of the appendix should clarify the point. Appendix B summarizes all the geometry you need to know and Appendix C explains the essentials of trigonometry.

Before we get into the first chapter, let me emphasize how important good survey practice is in construction. We've all heard sad stories about homes, apartments or garages that have been built on the wrong lot or straddling a property line. Fortunately, that's not a common error. But it's nearly always a very expensive mistake. Much more usual are foundations that aren't level, slab corners that aren't square, circles that are more like ellipses and ellipses that aren't like anything at all. These all begin with survey mistakes. But that's just the beginning. Anything that's not level, square and true in construction tends to affect every part of the job that follows. You begin with a foundation wall that isn't square at a corner and end up with roof sheathing panels that don't fit right.

The surveyor on the job has the first chance to make a mistake. If he (or she) does it right, the first error has to be made by someone else. Survey and layout that are done with care and professionalism promote craftsmanship throughout the project. What's the best way to be sure the survey and layout are done right? It's to do it yourself, or at least check it yourself. Maybe that's why some of the best, most successful contractors and builders I know have taken the time and trouble to learn construction surveying and layout.

Having said that, it's time to get down to business. We'll begin Chapter 1 by introducing land survey terms and concepts. By the time you've worked your way through this manual to the end of Chapter 15, I think you'll agree that construction surveying doesn't have to be difficult. There's nothing technical or theoretical here, but there's a lot to remember. Between Chapter 1 and Chapter 15 I'll explain it all, easily remembered.

Chapter One
Introduction to land Surveying

Land surveying allows a surveyor to precisely determine the area of any part of the earth's surface, the lengths and bearings (direction) of all the boundary lines, the contours of features of the land, and to accurately describe all of this information on a map.

A knowledge of surveying is indispensable if you are a builder, contractor, or developer. Not only will you often need to hire surveyors, check their findings, and read survey data and maps, occasionally you may be both the builder and the surveyor on a project. There's certainly no better way to find out about every aspect of the site you're developing.

This book describes the mathematics behind surveying, the instruments used to take measurements, the method for surveying a site, and the procedure for drawing accurate maps. You'll learn how to take complex measurements for roads, buildings, and bridges; how to establish grades for areas of cut and fill; and how to solve problems that may occur during a survey. The first thing you'll find out is how surveys actually started in the United States.

The History of U.S. Land Surveys

Land surveys made by government authority follow a definite system provided by law. These are United States Land Surveys. They began on May 18, 1775, when the Continental Congress called for a method of measuring and disposing of some lands claimed by the state of Virginia, which at that time included areas of West Virginia, Kentucky, and Ohio.

The Rectangular System

Accordingly, the Manual of Instructions for the Survey of the Public Lands of the United States was developed. It describes the conditions of the rectangular system of surveys that is required for U.S. land surveys.

Longitude and Latitude  The rectangular system uses the longitude and latitude lines of the earth as its base. The longitude lines, called meridians, run north and south from pole to pole and at 90° to the equator.

Latitude lines, called parallels of latitude, run east and west around the earth parallel to the equator. The equator is 0°. Parallels of latitude are 90° north of the equator (north latitude) and 90° south of the equator (south latitude). Longitude and latitude are stated in degrees, minutes, and seconds.

Initial Points  Under this system the initial point of a survey is referenced by longitude and latitude by astronomical methods, and marked accurately, called monumenting. This is done so that it's easy to identify exactly where the survey was started and, thus, exactly which piece of land is being described.

Initial points were established throughout the public domain by monumented meridian lines and baselines. Each meridian is identified by a name and number. These are listed in the manual of instructions.

All of the lines in the rectangular system are tied into or extended from these principal meridians and the baselines. They are identified as guide meridians and standard parallels, township exteriors, section lines, and meander lines (established by the water line of a lake or stream). In recent years, county officials have required that surveys be referenced to the legal comers of townships, and bearings and distances given in the deed (legal description) such that the surveyed area be satisfactorily closed by one of several methods ( which will be explained later).

Land Divisions The rectangular system was first used to survey Ohio. It began at the point where the Ohio River leaves Pennsylvania.

The public lands are divided into counties. Counties are divided into townships. Townships (6 miles square) are divided into 36 sections (1 mile square). Sections are divided further into quarter sections.

And, quarter sections are divided into quarter-quarter sections (see Figure 1-1). As always, there are a few exceptions to the rules. For instance, in Louisiana the word parish is used instead of county. And, sometimes townships aren't divided into exactly 36 sections.

A county contains townships, and a north-south row of townships constitute a range of townships. An east-west row of townships constitute a tier of townships. Figure 1- 2 shows the arrangement of the 36 sections in a township.

Figure 1-3 illustrates the political subdivision of land. The township boundaries running north and south, as ab, are intended to be true meridians and are called meridional boundaries. A series of townships in a north-and-south row constitute a range of townships. Therefore, the meridional boundaries are commonly known as range lines .

Townships are numbered as ranges in both east and west directions. Here they run west from the principal meridian, hence the letter W. Townships also are numbered as tiers both north and south, beginning with number one at the baseline.

You can see that Jackson Town-ship in the northwest corner is in Range 19 West (R-19-W), and in Townships (tier) North (T-7-N).

Look north to south along the west county line. You’ll see an example of mixed section numbering shown along the Jackson and Liberty townships. In Jackson Township, section 19 has a section 20 on either side of it. Section 30 has a section 31 on either side of it. This seemingly odd-numbered section is due to a land trade made with Pike County many years ago. You'll find this jumbled numbering in many places. There are localities in Ohio where the range lines run east and west and the township tiers run north and south. And, some townships there contain 25 sections instead of 36 sections. So, when you're researching area records, look out for the unusual.

Land Deeds

This rectangular system of surveying with official requirements was created because surveys are used as the basis for the land descriptions used in deeds. A deed is a legal document describing a certain piece of land that you own. So, if everyone used a different method of surveying for describing that land, no one would be sure who owned what.

Deeds describe the initial point of the survey and use bearings to describe the boundaries of the land in question. Figure 1-4 shows how a survey plane is divided into four quadrants, each 90°. The bearing is then referenced for every case, from the north-south line. For instance, bearing N30°E runs north by east 30° from the north-south line and bearing S30°W runs south by west 30° from the north-south line.

Suppose that you are about to buy a piece of land in the northwest area of the south half of the township shown in Figure 1-3, which is in Range 19 West of Jackson Township. You and the owner have visited or driven around the area you plan to buy. You then hire a surveyor to describe the boundaries of that piece of land. Your deed to the land will be written from the description made by the surveyor.

Since this parcel of land is in the northwest quarter (NW 1/4) of the southwest quarter (SW 1/4), the introductory paragraph of your land deed will read:

Being a parcel of land in the NW 1/4 of the SW 1/4 of Jackson Township, Jackson County, Ohio, R-19-W, T-8-N.

You can see the T-8-N (Township Eight north) on the south line of the township. This is an accurate legal description, written from a correct survey, that identifies this parcel of land from any other parcel anywhere on earth (See Figure 1-1).

To make it even better identified, the survey is tied to an initial, permanent point (described previously). In this case, the legal comer (any comer of a political subdivision) provided by the northwest comer of the NW 1/4 of the SW 1/4 of Jackson Township, is a perfect reference point for the survey of your land. Therefore, the legal description following the introductory paragraph in your deed reads as follows.

Beginning, for reference, on a stone at the NE comer of the NW 1/4 of the SW 1/4 of Jackson Township,

Thence 500 feet due south along the east line of said 1/4-1/4 to a point in said line; 

thence 356 feet due west to an existing fence comer, said comer being the place of beginning for this survey.

thence N84°23'W along a fence line a distance of 165 feet to a point in said fence line;

thence S5°19'25.51"W a distance of 276.66 feet to a point in an open field;

thence S84°23'E a distance of 165 feet to a point in an open field;

thence N5°19'25.51"E a distance of 276.66 feet to a point, said point being the fence comer at the place of beginning for this survey, said survey containing 1.05 acres, more or less.

Notice that in descriptions of a survey bearing, the words north, south, east, and west, are not used alone. For instance, the bearing on the east line of the 1/4-1/4 (Figure 1-5), is described as being "due north." This is the back bearing for the bearing given as "due south" in the deed description. Always use the word "due" with the cardinal direction.

Now you know how surveys began and how they are used to write deeds. The next step is to find out how to do a survey using the instruments and methods described in the following chapters.

Introduction | Table of Contents | Back Cover

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